Recently, technologies in which parameters related with such bodies in a real space as humans and things are measured by some means and the results thereof are captured as an input value in a computer for analysis and displayed as images are used in a variety of fields. In the field of computer games, intuitive and easy operations have been realized by acquiring the movements of a user himself or herself and the marker held by the user and accordingly moving characters in a virtual world inside a display screen (refer to PTL 1 for example). The technologies for reflecting the movement and shape change of a body in a real space onto a display image are expected for the application not only to games but also to toys and learning tools (refer to NPL 1 and PTL 2 for example).